An odd rock found in central Mississippi is rewriting the state’s Ice Age historical past — and even calling into query some long-held scientific assumptions.
It’s a piece of petrified wooden, however that’s not what has geologists excited.
Closer inspection has revealed the fossil is a lot, a lot older than the soil that surrounded it, state geologists say, maybe by thousands and thousands of years.
It’s nearly as if somebody introduced an already historic fossil to Mississippi, dug a deep gap and buried it for a number of hundred thousand years.
How did it get there?
It was carried, or relatively, “bulldozed,” in keeping with James Starnes, director of floor geology for the Mississippi Office of Geology.
He got here to that conclusion after observing the stone’s floor, which he says proves it was dragged a whole lot, if not 1000’s, of miles on the underside of a glacier.
“Nobody thinks about Mississippi and glacial ice in the same sentence. Not even most scientists. We are literally just figuring out the details of this time with these clues,” Starnes informed McClatchy News.
“It was always thought that the petrified wood in Mississippi was wood that was deposited with gravel and then fossilized, so it has to be the same age as the gravel,” he says. “The fact (this fossil) is faceted proves it was fossilized well before it was dragged under the glacier and then brought to Mississippi. That makes it much older than that deposits it was found in.”
Questions at the moment are piling up about the fossil, together with its age, what sort of tree it was, the place it’s from and when it was dropped in Mississippi.
However, Starnes says the most vital query is if this discovery means scientists have been mistaken to make use of petrified wooden from gravel deposits to check previous environments.
Mississippi’s glacial previous
There have been no glaciers that got here as far south as Mississippi.
Instead, the Mississippi River served as a big drainage ditch way back to 700,000 years in the past for glaciers all through the Pleistocene Age, consultants say. The river was 200 ft larger than it is now and ran as much as 15 miles east of its present location, based mostly on the placements of gravel deposits.
These deposits — a few of that are 100-feet thick — have been actually the backside of the Mississippi River throughout the Ice Age.
During the period, the river was the risky centerpiece of a treacherous panorama, Starnes says.
“This included catastrophic ice-dam breaks and ice-burgs flowing down to the Gulf of Mexico,” he says. “Megafloods from glacial meltwaters and ice-dam breaks entering the Mississippi River Valley were commonplace, as it drained a sheet of ice over a mile thick into the Gulf of Mexico. The river carried with it a flood of materials bulldozed by ice.”
It was amid that particles the fossil wooden found its approach to the Magnolia State, maybe scraped from some valley flooring 1000’s of miles to the north.
‘Needle in a haystack’
Starnes likens the discovery of the petrified wooden to “finding a needle in a haystack.”
The stone was found by state survey geologist Jonathan Leard a month in the past, in a “massive” gravel deposit close to the Hinds/Warren county line, Starnes says. The web site additionally holds big boulders, some weighing greater than a ton, that have been pushed south — or “ice rafted” — by violent glacial flooding, he says.
Some of the boulders at the moment are on show outdoors the Mississippi Museum of Natural Science.
The piece of faceted fossil wooden — the first of its kind found in the state — is additionally at the museum, as a part of a analysis assortment, he says.
“The few studies done on the petrified wood (found in state gravel deposits) have been used to reconstruct ideas of the environment when they were deposited. But this wood was petrified long before it was dragged underneath a glacier, which tells us it was from an even more ancient environment,” Starnes says.
“Any past assumptions based on the studies of petrified wood from these deposits now has to be called into question. We were wrong in thinking the fossil wood would be helpful with understanding the climate.”